1. FieId of the Invention
This invention relates to a head-gimbal assembly in a hard disk file. More particularly, the present invention relates to a load beam in the head-gimbal assembly.
2. Description of the Prior Art
A head-gimbal assembly (HGA) used in a hard disk file consists essentially of three components. The first component is a slider which features a selfacting hydrodynamic air bearing and an electromagnetic transducer used for recording and retrieving information from a spinning magnetic disk.
The second component is a gimbal which is attached to the slider. The gimbal is resilient in the slider's pitch and roll directions to allow the slider to follow the topography of the disk which it is flying over. Also, the gimbal is rigid in the yaw and in-plane directions for maintaining precise inplane slider positioning.
The third component is a load beam which is attached to the gimbal and to a support arm. The load beam is resilient in the vertical direction. This resiliency also allows the slider to follow the topography of the disk. As with the gimbal, the load beam is rigid in the in-plane directions.
The load beam also acts as a spring supplying a downward force that counteracts the hydrodynamic lifting force developed by the slider's air bearing. In order to produce this counteracting force, the load beam is provided with a single bend so that it urges the gimbal and slider towards the disk. However, ideal operation of the HGA in the loaded state (i.e., when the rotating disk is up to speed and the slider is flying above the disk) requires the load beam to have great in-plane stiffness and rigidity. To achieve ideal in-plane stiffness and rigidity, the load beam should be completely flat when it is in the loaded-state. If the load beam has excessive contours and curves or waviness when operating in the loaded state, it has poor in-plane rigidity and is a frequent source of troublesome vibrations and resonances.